define
(    
    function()
    {        
        AddSoundAction = function(soundUrl)
        {
            this.toJSON = function()
            {
                return {id: this.id, soundUrl: soundUrl};
            };
        };

        AddSoundAction.prototype.id = AddSoundAction.id = "AddSoundAction";
        return AddSoundAction;        
    }
);